package chapter10.login;

import java.sql.*;
import java.util.Scanner;

public class login {
    public static void main(String[] args) throws SQLException{
        Statement stmt = null;
        ResultSet rs = null;
        Connection conn = null;
        try{
            //1. 注册数据库驱动
            Class.forName("com.mysql.cj.jdbc.Driver");
            //2. 通过DriverManager获取数据库连接
            String url ="jdbc:mysql://localhost:3306/jdbc?serverTimezone=GMT%2B8&useSSL=false";
            String username = "root";//数据库账户
            String password = "123456";
            conn = DriverManager.getConnection(url,username,password);
            /**
             * 终端用户登录
             *不绑定数据使用conn.creat
             */
            Scanner sc = new Scanner(System.in);
            System.out.println("用户登录");
            System.out.println("请输入你的姓名");
            String userName = sc.next();
            System.out.println("请输入你的密码");
            String userPwd = sc.next();
            String loginSql = "select * from users where name=? and password=?";
            PreparedStatement pm = conn.prepareStatement(loginSql);
            pm.setString(1,userName);
            pm.setString(2,username);
            rs = pm.executeQuery();
            System.out.println("id     |    name    |   password   |  email   |   birthday");
            while (rs.next()){
                int id = rs.getInt("id");//通过列名获取指定字段的值
                String name = rs.getString("name");
                if (id>0){
                    System.out.println(name +"登录成功");
                    //如果数据库中有两个同名同密码的人 直接结束循环 只提示第一人
                    break;
                }
            }
        }catch (ClassNotFoundException e){
            e.printStackTrace();
        }finally {
            //6.回收数据库资源
            if (rs != null){
                try{
                    rs.close();
                }catch (SQLException e){
                    e.printStackTrace();
                }
                rs = null;
            }
            if(stmt != null){
                try{
                    stmt.close();
                }catch (SQLException e){
                    e.printStackTrace();
                }
                stmt = null;
            }
            if(conn != null){
                try{
                    conn.close();
                }catch (SQLException e){
                    e.printStackTrace();
                }
                conn = null;
            }
        }
    }
}
